1slow01Z71

iTrader: (36)

Oh I dont doubt that they fail, Ive read before that they do, just playing the probability game. With as many people on the performance forums that beat the hell out of their vehicles far beyond the average user there arent any people that Ive read of having the lifters fail on stock cams. You would think if theyre that bad then atleast one case would be documented on the forum. The only way he can truly be sure that he wont have a problem obviously is to delete them and run an LS7 replacement, me personally I wouldnt worry about it.

viciousknid

iTrader: (8)

One thing to consider is that most people on the threads don't have a stock cam any more and have already deleted AFM. FWIW

slammed89swb

Not meaning to tread jack but, I just got my AfM turned off when wheatley tuned my truck and its shifting at 6000... Should I be worried??? 48000miles, would be a shame to lose my 50,000 miles of remaining warranty... Your thought's gents? Stock cam 5.3

supercharged680

iTrader: (1)

a friend of mine has a 09 sierra with bolt ons has afm off and is shifting at 6200 with stock internals with no problems

Preston129

iTrader: (3)

When they're pumped full of oil, the AFM lifters are essentially doing the same thing and should be as strong as the non-AFM ones (at least in terms of the spring pressures they see in a stock engine). It's really only above .500" valve lift that the AFM lifters are going to be at severe risk for failure but since OP doesn't want to change cams, it's really a non-issue.

Robert91RS

iTrader: (2)

I will admit the others have valid points so it comes down to personal prefference I suppose. I will not be trusting them in my personal vehicle but will also be doing a cam and tune at the soonest opportunity. I have the utmost respect for everyones opinion on the matter but to me it just isn't worth the risk if you know your warranty is void and plan to push your vehicle.

BTW the first thing the tech will do after diagnosing a lifter problem on your truck is send your tune parameters to GM to check for an aftermarket tune.

1slow01Z71

iTrader: (36)

If you retrun the PCM back to a stock tune can they tell its been tuned on these newer vehicles? I know on the diesels they can but gas I havent read.

Robert91RS

iTrader: (2)

If they look hard enough the answer is a definate yes. What seems to be unclear at this point is how hard they look most times. These new ECMs have a flash counter and odometer that may go unnoticed but its going to be a risk.

1slow01Z71

iTrader: (36)

I guess they caught on to people just swapping clusters to have lower mileage vehicles

Robert91RS

iTrader: (2)

That was part of it but it also keeps you from swapping ecms. If you put 20k miles on a ECM with a aftermarket tune but swap it back to the factory ecm before heading to the dealer for warranty repairs it won't match the mileage on the cluster.